Pulp burial-casket and process of making same



(Specimens.)

G. E. SHAW. PULP BURIAL GASKET AND PROCESS OF MAKING SAME.

Patented Nov. 6, 1894.

as a i .ket'and forms an integral part of the body of UNITED STATES ATENT GEORGE E. SIIAW, or CINCINNATI, OHIO.

PULP BURlA L-CASKET AND PROCESS OF MAKING SAM.

SPECIFICATION, forming part of Letters Patent No. 528,612, dated November 6, 1894..

Application filed May 21, 1894- Serial No. 612,006- (No model.) 4

' as an article of manufacture, sale, and use,

possessing qualities not possible to be attamed by either wood or metal, and certain other qualities, especially desirable for this purpose, not attainable in pulp-material utilized in any of the methods of manufacture in vogue. a

To these ends, my invention consists in a' burial casket and the method or process of manufacture of the same from a pulp composed of vegetable fiber, preferably straw, as hereinafter described andclaimed.

The casket, when made as herein described of this material, requires no further treatment, except to be finished externally with oil, varnish, paint, &c., or covered and ornamented in any suitable manner. The main 3 body or foundation, however, of the ornaproduct, is simultaneous external compl es ment may be produced in and during the process of manufacture, by designs formed upon or recessed into the faces of the compression dies or'plungers, employed in the man ut'ac- ,ture; whereby the counterpart of such'designs is produced in or upon the surface of the casthe, structure.

-, 'I-n-"theprefer'red process of manufacture, the pores of the structure'are filled withselfhardening adhesive material which is caused by-heat and moisture to flow into the inter-' stices and permeate the material throughout. The nature of the invention willbe more fully understood from the subjoined descriptioii inconnection with the accompanying drawings, in which- 4 Figure 1, is a side elevation of a specimen of my improved burial casket; Fig.-2,an end elevation of the'same; Fig. 3, a cross section of the same. Figs. 4 and 5, are a diagram plan section and a vertical cross-section respectively, of a compression machine,'illus tr'ating certain essential principles of the manufacture; and Figs. 6, 7, and8, enlarged details further illustrating certain features.

The pulp, made in the usual manner, in suitable pulp-mills, consists of the disintegrated fibrous constituents of the material mechanically suspended in water. A predetermined quantity of this pulp is fed into the chambers a of a. compression machine provided with reciprocating plungersfib, arranged about asuitable core or former, c, and' by a simultaneous compressive movement of the plungers, the material is compressed to form,

about the core, and the water excluded by pressure and heat, forming the casket, A, illustrated in Figs. 1, 2, and 3.

For the purposes of the present application, Figs. 4, 5, 7, and 8, will sufiiciently illustrate the essential characteristics of the compres 1 sion apparatus employed in carrying out my invention, which apparatus, inasmuch as it differs from compression apparatus for which I have already filed an application for Letters Patent only in certain features herein specified, is illustrated only in respect to said features.

As one of the fundamental features of the process, affecting the nature of the ultimate sion ofthe material about the core, in, substantially, the projected axes of the plane sides .and bottom of the casket, four of the.

compression chambers (eachhaving a crossarea corresponding in form and dimensions with the side in whose axis it is pro ected) are arranged in a common horizontal plane (Fig. 4:) about the central core, 0, (corresponding in form and dimensions with the hollow. interior of the casket body.) The plungers, b, fitting the several chambers are provided with suitable means, (such, for example, as cylinders with pistons operated therein by liquid or other pressure,) adapted to move the plungers inward simultaneously'to a given limit, allowing proper thickness for the shell of the compressed casket body, A, so that. the

edges of the plungers meet and define the corners of the casket.

A vertical compression chamber, a, with plungers, b, is also arranged above the core,

too

c, (Fig. 5) to form the bottom of the casket body, A, and said plunger meets edge to edge with the other plungers at the ultimate limit of movement defining the bottom corners of the casket.

In plunger machines, heretofore constructed, the walls of-adjacent plunger-chambers meet at a sharp edge, as illustrated in Fig. 6, in which, e, e, designate the meeting walls of adjacent chambers, an d, f, their meeting edge, (f also designating in the case of a product having angular corners, a corner of the compressed body, At) Now, in the com-,

pressive movement of the plungers, b, from the position shown, to their limit of movement (the outer faces of the body, A,) it will be seen that the action tends to produce, in the compressed product, a line of division between the compacted fibers,- extending into the shell, A, diagonally from the corner, f; and the greater proportion of the fibers at the end of the mass in one compression chamber are by the conditions of structure, held apart from those of the adjacent compression chamber; and, excepting those of the inner layer of the casket, they are given no opportunity to coalesce or interlock, but are simply brought together, as compression proceeds, with less and less force to the extreme outer layer, in which the ultimate movement of the plungers simply brings the fibers to the point of contact without any compression together. These conditions exist also in circular or other structures produced by radially arranged compression plungers. As a result of this inherent structural defect in this general type of machines that compress by means of plungers, in the manner described, about a core, a product of no practical value is produced because the subsequent shrinkage of the material opens the corners or places in the periphery where the described action took place; and, as a result, machines of this class have commonly been regarded as failures. In my improved casket body, this defeet is completely remedied and the corners are made even stronger and more compact, by introducing and forcing into the casketshell at the corners, an additional body of material, in the process of compression, in such manner as to completely fill the otherwise vacant space and interlock with the fibers at both sides. The constructive features incident to this part of the improvement are illustrated in Fig. 7, that is to say: I chamfer away the meeting edge or corner formed by the walls of adjacent plunger chambers, to a line, as, y, thus forming a triangular space w, y, f, extending the entire length of the meeting walls, and outside the normal limits of the plunger action. As the plungers, I), move inward, the pulp in this space becomes so far compacted with the main body of pulp in the chambers, that, as the plungers reach the points, any, and move toward their meeting point, f, the pulp of the triangular space is carried forward and diagonally forced inward into the body of pulp on either side, and bent to form the actual corner of the casket body; and in so doing, its fibers are forced into interlocking relations with those on either side. By this means, and by the additional material thus forced into the mass, the corner of the casket is rendered even stronger and more dense and as perfect as the rest of the, casket body, and there is no break in the interlocking continuity of the fibres. Suitable provision for drainage is also made, so that the water contained in the pulp may readily escape, as is necessary in the manufacture of pulp articles. This is eifected, preferably, in the following mannerz-For the convenient application of heat presently to be explained, I prefer to employ imperforate plungers, b, and core, 0; and, in order to eifect the desired drainage at both sides of the mass under compression, I employ external minutely perforated plates, 17, (Fig. 8) channeled atthe under side, as facings for both the pluugers and the core. The water expressed from the pulp material at the core'side, passes through the perforations of the facing plates to the channels adjacent to the imperforate surface of the core, and escapes below. That passing through the facing plates of the side plungers, drains out below in like manner. The ultimate drainage of the plunger-side of the bottom of the casket is provided for by a series of minute perforations, 0, through the shell of the upper plunger chamber above the line of contact of the edges of the chamber with those of the side chambers.

The fundamental characteristic of extreme density of the casket body is largely due to the direct application of heat during compression, at both sides of the casket shell; so that continued compression follows up the exclusion of moisture and natural shrinkage and thoroughly desiccating the outer layers and compacting the fibers more perfectly, thus rendering the product dense and non-porous and producing a casket free from any subsequent tendency to warp or crack.

In the manufacture of articles from pulp, it has been common to employ heat,but only at one side of the shell produced. This method of heat application desiccates one side of the structure, producing an unequal texture, causing it to warp. In small articles, such as have heretofore been produced from pulp, this difficulty has been suificiently overcome for the uses of such articles, by a subsequent oil-soaking and baking process, termed indurating; but such would not be practicable with burial caskets, as it weakens the fiber, besides being too expensive. I I find, however, that the application of heat in the manner described herein, in connection with the other features of the process, afiiords a perfect remedy for this difliculty and produces a layer of the fibrous pulp having outer surfaces of relatively greatest density and desiccation and a corresponding texture thence inwardly,

and which is approximately free from a tend.-

.ency to warp. To this end, the movable nicated by direct contact of themetal plungem and core; and the material is at the same time further compacted by pressure to assist natural shrinkage.

In proceeding to form a casket, the pulp material contained in sufiicient'waterto enable the fibers to assume natural positions, is introduced around the core, in the chambers, a, in front of the now-withdrawn plungers, b, so as to completely fill all the space to the exclusion of air. Power is then simultaneously applied to the lateral andvertical plungers and the liquid material subjected to pressure, which gradually forces outthe contained water at the screen-faces ofthe core and plungers, and the fibers gradually settle and become compacted in the relationsnaturally assumed, inasmuch as the pressure is at all times perpendicular to the plane of-the layer produced. (In this case, it is desirable to give a slight flare to the sides of the casket and therefore the faces of the lateral plungers are correspondingly inclined; but the angle is so slight as not to afiect the general principle.) After'the water has been substantially excluded, and the compression has proceeded to a point approximating the limit of movement, of theplungers, steam is admitted to the plungers and core, simultaneously; and sufficient heat is'thus' directly communicated to the compressed layers to vaporize the remaining moisture while the compression proceeds to its full limit; .thus following up the natural shrinkage and more thoroughly compacting the material.

The manufacture, as thus described, produces a casket, practicable and useful 'inall respects, and ready, when treated with oil, varnish or other finish, for the market; but, 'amore perfect product may be produced by first mixing with the "pulp used, a suitable quan- .tity of'starchy substance, finely pulverized and mixed with cool water, and thoroughly disseminated through 'the pulp. The process proceeds in all respects,as hereinbefore de-- scribed; but in the final part of the process, a further action takes place, namely: the moist starchy substance, contained in the liq-; uid material,-is, by heat, applied as described, cooked and caused to swell and burst its cell-structure; and, by such swelling, produces an internal pressure, causing the resulting pasty mass to permeate and fill the minute interstices of the casket body; and, by its adhesive quality, when subsequently dried and hardened, cement the whole together.

When the compression is fully completed, and a limited time allowed for drying, the casket is removed from the apparatus and treated with oil, varnish or paint, or otherwise, to give the desired finish. The ornamental finish,'as to form, is, however, already produced in the material by the recessed dies, as before indicated and an external appearance of great elegance is thus cheaply produced.

' The casket thus produced, diifers from ordi- -nary articles produced from pulp-materialin being much stronger and more durable by reason-of the perfect interlocking of the fibers throughout, especially at the angles and corners, and is more durable, in respect to atmospheric and other influences, by reason of its more dense, compact and desiccated structure resulting from the simultaneous action of heat and pressure, whereby, its porosity being practically eliminated and its structure being uniform, it has no tendency to warp or shrink. Finally, the burial casket, embodying these desirable qualities, and in an ornamental form realizing the highest attainment of artistic design, is produced complete at the minimum of cost, and in practically unlimited quantities, as an article of manufacture within the reach of all.

.In, the manufacture of articles as herein described the pulp in a fluid state is fed into the upper plunger chamber by suitable deliverypipes when all the plungers are withdrawn, and thence flows around the core and into the'spaces in front of the plungers.

I claim as my invention, and desire to secure by Letters Patent of the United States, as follows:

1. A-burial casket or other article of cominwardly, and being thereby approximately free from a tendency towar -substantially as set forth. I

2. The improvement in the art of forming articlesfrom semi-fluid fibrous pulp, and removing the tendency to warp, consisting in subjecting thelayer of material to compression with equal and uniform drainage at both sides, and to heat at both sides during final compression following upthe' natural shrinkage, substantially as set-forth.

3. The improved process of forming a burial casket or other article from semi-fluid fibrous 'pulp, consisting in mixing with the pulp while cold a starchy substance and.by heat applied during compression causingt-he same .under the influenceof heat and moisture to swell andpermeate the interstices and become disseminated through the mass, substantially as set forth.

4. The improvement in the art of forming box shaped articles from semi-fluid fibrous pulp and strengthening the corner angles, 7 Intestimonywhereoflhaveherenntoset lny consisting in forcing additional material into hand in the presence of two subscribing witthe mass under compression at the j unetion messes.

of sides, ends, and bottom, simultaneously, GEORGE E. SHAW. during the compression of the body layer, to \Vitnesscs: constitute the outer angles of said junction, LANDON FREYBLER,

substantially as set forth. L. M. HOSEA. 

